Dump trailer



Dec. 17, 1940 H. c. KEITH DUMP TRAILER Filed Jul 's, 1940 2 Sheets-Sheet 1 In ventor tiomey Dec. 17

H. c. KEITH DUMP TRAILER Filed July 5, 1940 2 Sheets-Sheet 2 Inventor Hi/V/E'Y C. A277 Attorney Patented DE- 17 DUMP TRAILER Henry 0. Keith, Markham, rm, assignol' o! fortynine per cent to Rufus M. Keith, Bay City,

' Application luly s, 1940, Serial No. 344,178

-1 Claim.-

My invention relates to improvements in dump trailer and the principal object in view is to pro.- vide a simply constructed, inexpensive, sturdy trailer with a low center of gravity upon which g heavy vehicles such as tractors and the like may be easily loaded for transportation on the road.

To the accomplishment of the above, and subordinate objects presently appearing, a preferred embodiment of my invention has been illustrated it) in the accompanying drawings, set forth in detail in the succeeding description and described in the claim appended hereto. I

In said drawings: Figure 1 is a view in bottom plan 'of the I! preferred embodiment of my invention.

Figure 2 is a view in side elevation.

Figure 3 is a fragmentary detail view in top plan drawn to an enlarged scale, d

Figure 4 is a view in perspective a modifica- 20 tion of the axle bar.

Referring to the drawings by numerals, my improved dump trailer comprises, as its basic element, an axle bar I, preferably in the form of a channel iron beam, provided on the ends 2 thereof with stub axles 2 upon whichare small diameter ground wheels 3 preferably rubber tired.

The axle bar I supports a flat bed 4 of elongated form disposed lengthwise across said bar and comprising a pair of longitudinally ex- 30 tending side bars I and a center bar 3 with cross planks I suitably secured thereon. The beams 5, 3, are hinged substantially midway of their ends to the axle bar I so that said bed 4 dumps rearwardly and downwardly. The hinges 35 comprise spring leaves 'i suitably secured, as at 3, to the under side of said beams l. 3, and pivoted, as at 3, between pairs of hinge bars i3, secured to the rear side of the axle bar i. The pivotal axis of the hinges described is close to the axle 40 bar i to contribute to a low center of gravity arrangement in .the trailer as will be clear. The bed 4 is of increased. width in the rear of the wheels 3 so that the bed is overbalanced to dump rearwardly and downwardly, and the beams I, 8. 45 are beveled, as at H, at their rear ends to abut the ground flush when the bed is dumped so as to facilitate driving a tractor, or the like, up said bed when dumped. Chock blocks i2 are provided at suitable corners of the bed 4 on top 50 thereof for preventing a tractor, or other vehicle, from overrunning the bed 4 when driven thereon. Eye-bolts l3 with rings i4 therein are also provided on the bed 4 for use in anchoring a tractor on said bed. 55 An underslung draft tongue It extends for- (01. ass-s) wardly from beneath the axle bar 4 braced by a pair of reach rods i3 secured thereto on opposite sides thereof. as at H, and having rear ends threaded, as at i2, and extended through axle bar I with nuts i3 turned thereon. The front end of the tongue i3. is provided with a suitable 5 clevis type hitch 23. An abutment block 2! on the tongue l3, under the front end of the bed 4, establishes the normal position of said bed.

An upstanding latch bar 22 is pivoted at its 10 lower end, as at 23, to a pair of brackets 24 bolted to the top of the tongue II, as at 23, the arrangement being such that said bar is swingable rearwardly and forwardly into and from latching position. The latch bar 22 is urged rearwardly toward latching position by means of a rod 26 having a rear end pivoted to said bar, as at 21, and a front end slidably mounted in a bracket 23 bolted to the top of the tongue I! as at 29.

A coil spring 23' surrounding the rod between said brackets 28 and a collar 33 on said rod urges the rod and hence the latch bar 22 rearwardly into latching position. A nut 3i threaded onto the front end of the rod 23 to abut the bracket 23 limits rearward movement of said rod. The 25 latch bar 22 is provided on the rear edge thereof with a down-turned beak 32 adapted to hook over a cross-bolt '33 extending between a pair of bars 34 projecting forwardly from the bed 4 and bolted, as at 36, to opposite sides of the center bar 6. The upper end of the latch bar 22 is formed with an upstanding hand grip 33 by means of which said bar may be swung forwardly to unlatohing position in which the beak 32 releases the bolt 33 and the bed 4 is free to 5 dump under the influence of gravity. As best shown in Figure 2, the beak 32 and hand grip 33 form a rearwardly and downwardly inclined cam 31 on the latch bar 22 adapted to be engaged by the bolt 33 with a wiping action under down- 0 ward movement of the front end of the bed 4, whereby said latch bar 22 is cammed forwardly to hook over said bolt with a snap action under the urge of the spring 23'.

Any suitable means may be provided for securing the tongue I! to the axle bar I, as for instance, a pair of cheek plates 38 bolted to the under side of the axle bar as at 33 and to the tongue as at 43.

As will be manifest, in the dumped position of the bed 4, shown in dotted lines in Figure 2,

a tractor, or other vehicle, may be driven up the bed 4 until it overbalances the front end of the bed, whereupon said bed will gravitate to normal position. As the front end of the bed 4 descends,

the bolt 83 coacts with cam 31, in the manner already described, so that when the bed reaches normal position, the beak 82 hooks over the bolt 83 unde the influence of the spring 29' with a snap action and said bed is latched against dumping. "I'o unlatch the bed it is merely necessary to grasp thehand-grip l6 and pull the latch bar- 22 forwardly to unlatching position already described.

In Figure 4 I have shown a modified form of axle bar 4| for converting the trailer into a four wheeled vehicle, said bar embodying a pair of cross bars 42 at opposite ends thereof, respectively, each carrying a pair of stub axles 43 for themounting of ground wheels, not shown,

thereon. The axle bar ll may be attached in What I claim is:

A dump truck comprising a wheel supported axle bar, a flat bed of elongated form including a pair of subjacent side beams and a center beam extending crosswise of said bar, hinges connecting the side beams intermediate the ends thereof to said bar whereby the bed is vertically swingable on said her into and from rearwardly dumped position, said bed fitting between said wheels and said hinges being attwhd to the rear side of said bar to lower the center of gravity of said bed, and said bed having a widened tail end portion for counterbalancing the same to cause automatic dumpingof the bed, an underslung tongue fixed to said bar centrally of the bar to extend forwardly beyond the bed, a transverse bumper bar on said tongue beneath the front ends of said beams for supporting the front end of the bed, and coacting devices on said tongue and front end of the bed-for locking the bed down against said bumper bar.

e HENRY C. KEITH. 

